Description The Sig Sauer M400 TREAD is a step in the right direction when it comes to entry level AR15 platform rifles. The rifle utilizes a mid-length direct impingement operating system and comes standard with features usually only found on premium priced rifles. The upper and lower receiver of rifle are made from aircraft grade 7075 aluminum and have been hardcoat anodized for long lasting durability.PRODUCT DETAILCALIBER: 5.56 NATO BARREL LENGTH: 16 in (292 mm) MAGS INCLUDED: (1) 10rd Polymer Mag MAG TYPE: AR-15 STATE COMPLIANT: Colorado (CO) ACTION TYPE: Semi-Auto STOCK TYPE: 6-Position SL-K BARREL MATERIAL: Stainless Steel TRIGGER TYPE: Single Stage Polished/Hard-Coat TWIST RATE: 1:08 FOREND TYPE: Alloy GRIP TYPE: Polymer RECEIVER FINISH: Hard Coat Anodized OVERALL LENGTH: 30.8 in [782 mm] OVERALL WIDTH: 2.5 in [64 mm] HEIGHT: 7.5 in (191 mm) ACCESSORY RAIL: M-LOK WEIGHT: 7 lbs (3.2 kg) Firearms, trailers, and some accessories are only available for purchase in stores. Each location follows all BATF and individual state/county/city laws to insure the desired product is legal for sale. Any info provided online is subject to change, please go to your local store for more accurate information.